#include<stdio.h>
#include<stdlib.h>
#include<pthread.h>

pthread_mutex_t mutex1= PTHREAD_MUTEX_INITIALIZER;
int counter =0;

void *fun()
{
	pthread_mutex_lock(&mutex1);
	counter++;
	printf("counter value:%d\n",counter);
	pthread_mutex_unlock(&mutex1);
	pthread_exit(0);
}

int main()
{
	int rc1,rc2;
	pthread_t thread1,thread2;

	if((rc1=pthread_create(&thread1,NULL,&fun,NULL)))
		printf("thread creation failed:%d\n",rc1);

	if((rc2=pthread_create(&thread2,NULL,&fun,NULL)))
		printf("thread creation failed:%d\n",rc2);
	
	pthread_join(thread1,NULL);
	pthread_join(thread2,NULL);

	exit(0);

}

